From patchwork Tue Apr 26 14:06:58 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "libaokun \(A\)" X-Patchwork-Id: 566474 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 6BE5DC433FE for ; Tue, 26 Apr 2022 13:52:52 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229840AbiDZNz5 (ORCPT ); Tue, 26 Apr 2022 09:55:57 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:40708 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1345563AbiDZNz4 (ORCPT ); Tue, 26 Apr 2022 09:55:56 -0400 Received: from szxga08-in.huawei.com (szxga08-in.huawei.com [45.249.212.255]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id C0A4A1353A6; Tue, 26 Apr 2022 06:52:47 -0700 (PDT) Received: from dggpeml500020.china.huawei.com (unknown [172.30.72.56]) by szxga08-in.huawei.com (SkyGuard) with ESMTP id 4Knjwn153Cz1JBly; Tue, 26 Apr 2022 21:51:53 +0800 (CST) Received: from huawei.com (10.175.127.227) by dggpeml500020.china.huawei.com (7.185.36.88) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2375.24; Tue, 26 Apr 2022 21:52:45 +0800 From: Baokun Li To: CC: , , , , , , , , , Hulk Robot Subject: [PATCH v2] ext4: fix race condition between ext4_write and ext4_convert_inline_data Date: Tue, 26 Apr 2022 22:06:58 +0800 Message-ID: <20220426140658.1046700-1-libaokun1@huawei.com> X-Mailer: git-send-email 2.31.1 MIME-Version: 1.0 X-Originating-IP: [10.175.127.227] X-ClientProxiedBy: dggems706-chm.china.huawei.com (10.3.19.183) To dggpeml500020.china.huawei.com (7.185.36.88) X-CFilter-Loop: Reflected Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org Hulk Robot reported a BUG_ON: ================================================================== EXT4-fs error (device loop3): ext4_mb_generate_buddy:805: group 0, block bitmap and bg descriptor inconsistent: 25 vs 31513 free clusters kernel BUG at fs/ext4/ext4_jbd2.c:53! invalid opcode: 0000 [#1] SMP KASAN PTI CPU: 0 PID: 25371 Comm: syz-executor.3 Not tainted 5.10.0+ #1 RIP: 0010:ext4_put_nojournal fs/ext4/ext4_jbd2.c:53 [inline] RIP: 0010:__ext4_journal_stop+0x10e/0x110 fs/ext4/ext4_jbd2.c:116 [...] Call Trace: ext4_write_inline_data_end+0x59a/0x730 fs/ext4/inline.c:795 generic_perform_write+0x279/0x3c0 mm/filemap.c:3344 ext4_buffered_write_iter+0x2e3/0x3d0 fs/ext4/file.c:270 ext4_file_write_iter+0x30a/0x11c0 fs/ext4/file.c:520 do_iter_readv_writev+0x339/0x3c0 fs/read_write.c:732 do_iter_write+0x107/0x430 fs/read_write.c:861 vfs_writev fs/read_write.c:934 [inline] do_pwritev+0x1e5/0x380 fs/read_write.c:1031 [...] ================================================================== Above issue may happen as follows: cpu1 cpu2 __________________________|__________________________ do_pwritev vfs_writev do_iter_write ext4_file_write_iter ext4_buffered_write_iter generic_perform_write ext4_da_write_begin vfs_fallocate ext4_fallocate ext4_convert_inline_data ext4_convert_inline_data_nolock ext4_destroy_inline_data_nolock clear EXT4_STATE_MAY_INLINE_DATA ext4_map_blocks ext4_ext_map_blocks ext4_mb_new_blocks ext4_mb_regular_allocator ext4_mb_good_group_nolock ext4_mb_init_group ext4_mb_init_cache ext4_mb_generate_buddy --> error ext4_test_inode_state(inode, EXT4_STATE_MAY_INLINE_DATA) ext4_restore_inline_data set EXT4_STATE_MAY_INLINE_DATA ext4_block_write_begin ext4_da_write_end ext4_test_inode_state(inode, EXT4_STATE_MAY_INLINE_DATA) ext4_write_inline_data_end handle=NULL ext4_journal_stop(handle) __ext4_journal_stop ext4_put_nojournal(handle) ref_cnt = (unsigned long)handle BUG_ON(ref_cnt == 0) ---> BUG_ON The lock held by ext4_convert_inline_data is xattr_sem, but the lock held by generic_perform_write is i_rwsem. Therefore, the two locks can be concurrent. To solve above issue, we just add inode_lock in ext4_convert_inline_data. Fixes: 0c8d414f163f ("ext4: let fallocate handle inline data correctly") Cc: stable@vger.kernel.org Reported-by: Hulk Robot Signed-off-by: Baokun Li --- V1->V2: Increase the range of the inode_lock. fs/ext4/inline.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/fs/ext4/inline.c b/fs/ext4/inline.c index 9c076262770d..0518edcfc0e1 100644 --- a/fs/ext4/inline.c +++ b/fs/ext4/inline.c @@ -2002,6 +2002,7 @@ int ext4_convert_inline_data(struct inode *inode) handle_t *handle; struct ext4_iloc iloc; + inode_lock(inode); if (!ext4_has_inline_data(inode)) { ext4_clear_inode_state(inode, EXT4_STATE_MAY_INLINE_DATA); return 0; @@ -2024,6 +2025,7 @@ int ext4_convert_inline_data(struct inode *inode) if (ext4_has_inline_data(inode)) error = ext4_convert_inline_data_nolock(handle, inode, &iloc); ext4_write_unlock_xattr(inode, &no_expand); + inode_unlock(inode); ext4_journal_stop(handle); out_free: brelse(iloc.bh);